Accelerator system

Field of the invention

The present invention relates to an accelerator system for use with vehicles.

Background of the invention

The driving of vehicles such as motorcycles and automobiles typically involves manually operating an accelerator which controls the power output of the vehicle motor. For example, motorcycles are commonly equipped with an accelerator in the form of a twist throttle whilst the accelerator of cars is usually in the form of a foot-operated pedal. However, the manner in which vehicle operators manually operate such accelerators may not be ideal and can be prone to human error.

For example, in the case of a motorcycle twist throttle, the twist throttle also functions as the right hand handle via which the motorcycle operator holds onto and steers the motorcycle. There are thus circumstances in which the rider's ability to control the power output of the motorcycle motor is compromised by having to hang onto and/or steer the motorcycle, and vice versa. One such circumstance involves the rider twisting the twist throttle and accelerating the motorcycle rapidly such that the rider's weight is thrown backwards and away from the direction of travel. As the rider's weight is thrown back the rider may inadvertently twist the throttle further in a manner that further increases the power output of the motor, thereby reducing the rider's control over the motorcycle. Moreover, since the left hand handle of the motorcycle is not configured to twist like the twist throttle, the rider is able to grip and pull on the left handle to steady himself or herself in a manner that may not be possible with the right hand twist throttle without also inadvertently altering the power output of the motorcycle motor. This asymmetry in the handling of the motorcycle can compromise the rider's control over the motorcycle.

There are also circumstances in which the effect of a traction control system is undesirable, and, in the case of a motorcycle, can compromise the rider's control over the motorcycle.

Embodiments of the present invention seek to improve a vehicle operator's control of a powered vehicle by giving them resistance to motion or effectiveness of, and possibly also feedback from, and movement of, the accelerator. The accelerator system could provide control over the steering of the vehicle as well so as to prevent feedback from the steering affecting the power application from the vehicle operator. The accelerator system may also provide control over suspension components in order to achieve the overall goal of allowing the operator of the vehicle to better modulate the power delivery of the vehicle. The braking functions and clutch functions could also be incorporated.

Summary of the invention

According to a first aspect of the invention, there is provided an accelerator system for a vehicle, the system comprising a manually operated accelerator, and force applying means responsive to an input and operable to apply an increased resistance to manual operation of the accelerator whereby to modify the relationship between the manual force required for manual operation of the accelerator and power output of the vehicle motor, wherein absent said manual force for manual operation of the accelerator, no modification of said relationship will occur. Accordingly, when the operator applies a manual force, inadvertent or otherwise, to operate the accelerator in a manner which could compromise handling of the vehicle, the accelerator system can act to resist that manual force and prevent or at least limit the extent to which handling of the vehicle may be so compromised.

Preferably, the force applying means is operable to increase the force required to be applied to the accelerator to effect manual operation thereof. It is thus possible to reduce the likelihood of the operator of the vehicle from inadvertently applying a manual force to the accelerator.

In certain embodiments of the invention, the force applying means is operable to lock the accelerator against manual operation thereof. As such, the vehicle operator can temporarily be prevented from affecting the power output of the vehicle motor. In the case of a twist throttle on a motorcycle then, even when the motorcycle is accelerating rapidly and throwing the weight of the rider backwards, the rider could grip onto the twist throttle and control the motorcycle without inadvertently twisting the twist throttle and adjusting the power output of the motorcycle motor.

In some embodiments of the invention, the input comprises or includes input applied manually by the operator of the vehicle. In such embodiments, it is envisaged that the vehicle operator can control when the accelerator system is operative to affect his or her manual control over the accelerator.

It is envisaged that the input could include an electrical input from a control unit programmed to be responsive to one or more dynamic conditions of the vehicle. As such, the accelerator system could improve the handling of the vehicle in response to a wide range of operating conditions instantaneously, thereby providing improved vehicle handling and safety across a wide range of situations.

Preferably, the control unit is programmed such that, in response to activation of a traction control system of the vehicle, the force applying means moves the accelerator to a position corresponding with the reduction in power output caused by the traction control system. As such, the accelerator system effectively moves the accelerator to a position which corresponds with the reduced power output caused by the traction control system.

In certain embodiments of the invention, the control unit is configured to output, to a steering damper system and/or a suspension system of the vehicle, information relating to one or more dynamic conditions of the vehicle such that the steering damper system and/or the suspension system acts to reduce the effect of the one or more dynamic conditions on the vehicle. For example, in the case of a motorcycle hitting a pothole, the handlebars of the motorcycle can oscillate violently. When this happens, the rider trying to hold on to the handlebars can exacerbate the situation. As the right hand bar moves towards the rider the throttle tends to be closed and as the bar moves away from the rider the throttle tends to be opened. Being at the same frequency as the handle bar oscillation the rapid opening and closing of the throttle can feedback and make the situation worse. Often in this situation deceleration can be the worst thing to do because it makes the motorcycle less stable. By using inputs from various sensors such as pressure sensors in the hand grips this situation could be detected by the system. For example, having sensed such oscillation of the handlebars, this information can be sent to the control unit, which can be programmed to output this information to the steering damper system and/or a suspension system of the vehicle such that those systems activate act to and dampen the oscillation of the handlebars.

In some embodiments of the invention, the force applying means is an electrical solenoid. However, it is also envisaged that the force applying means could be an electric motor connected to the accelerator. Preferably the electric motor is a stepper motor due to its relatively high holding torque which is particularly suitable for resisting manual force applied to the accelerator.

In preferred embodiments of the invention, the accelerator is electrically connected to the motor of the vehicle to thereby control power output thereof. The accelerator system may also comprise a force sensor for sensing the manual force applied to the accelerator, wherein the amount of force measured is used to vary the power output of the vehicle's motor and/or to vary the operation of the force applying means.

Preferably, the force applying means is additionally operable to move the accelerator while manual force is applied thereto. For example, it is envisaged that if the vehicle operator applies a manual force to move the accelerator in a particular direction when handling of the vehicle may actually be improved by moving the accelerator in an opposite direction, the force applying means may act not only to resist the operator's applied manual force, the force applying means may also override that manual force and cause the accelerator to move in the opposite direction.

In certain embodiments of the invention, the force applying means applies a frictional braking force between the accelerator and a component relative to which the accelerator moves when in operation.

In embodiments of the invention, the force applying means is operable to: lock the accelerator against manual operation which would increase the power output of the motor; and/or apply an increased resistance to manual operation of the accelerator which would increase the power output of the motor. In this way, the accelerator system acts to resist or prevent the operator from increasing the power output of the vehicle motor.

Preferably, the accelerator is a twist throttle and the aforementioned force sensor is a torque sensor which senses the torque applied by the operator to the twist throttle.

According to a second aspect of the invention, there is provided a system comprising a manually operated accelerator, and force applying means associated with the accelerator and responsive to an input to control movement of, or apply resistance to movement of the accelerator, whereby to modify the relationship between input force applied to the accelerator by the operator of the vehicle and power output of the vehicle motor, the input comprising a manual force applied to the accelerator by the operator whereby absent said manual input no modification of said relationship will occur, wherein if no force is applied to accelerator by the operator of the vehicle, the accelerator returns to an idle or no power position. As such, if the operator applies a manual force, inadvertent or otherwise, to operate the accelerator in a manner which could compromise handling of the vehicle, the accelerator system can act to resist that manual force and prevent or at least limit the extent to which handling of the vehicle may be so compromised. Moreover, if the operator applies a manual force to move the accelerator in a particular direction when handling of the vehicle may actually be improved by moving the accelerator in an opposite direction, the force applying means may act to override that manual force and cause the accelerator to move in the opposite direction. Moreover, just as foot pedals of cars and twist throttles of motorcycles return to an idle or no power position when unactuated, so too does the accelerator of the present accelerator system.

It is envisaged that the input includes an electrical input from a control unit programmed to be responsive to one or more dynamic conditions of the vehicle. As such, the accelerator system may improve vehicle handling and safety under a wide range of operating conditions instantaneously. Dynamic conditions of the vehicle may include any one or more of the following :

the speed of the vehicle;

the acceleration of the vehicle;

information relating to the torque applied to one or more wheels of the vehicle; and

the geographical position of the vehicle.

It is also envisaged that the input to which the force applying means is responsive can include information relating to the position of the vehicle operator's body and/or the forces under which his or her body is under. To this end, the accelerator system comprises sensors for sensing the position of the vehicle operator, and/or the forces experienced by the operator. For example, in the case where the vehicle is a motorcycle, pressure sensors of the system may detect the pressure with which the operator is grasping the handles and/or the weight of the operator on the motorcycle seat.

In certain embodiments of the invention, the accelerator system communicates with or includes a GPS and/or lookup tables to determine a target speed of the vehicle. As such, the system could act to reduce the likelihood of the vehicle exceeding speed limits.

It is common for vehicles to be equipped with traction control systems which adjust the power output of the vehicle motor based on the traction, or lack thereof, between one or more wheels of the vehicle and the surface on which it is being driven. In such vehicles, it is envisaged that the accelerator system of the present invention can communicate with the traction control system, wherein input to which the force applying means is responsive includes information relating to traction. In certain embodiments, the accelerator system of the present invention may be configured such that if the operator overcomes the resistance or movement applied by the force applying means, the traction control system may be deactivated.

Preferably, the control unit is programmed such that, in response to activation of the traction control system, the force applying means moves the accelerator to a position corresponding with the reduction in power output caused by the traction control system. As such, the accelerator system effectively moves the accelerator to a position which corresponds with the reduced power output caused by the traction control system.

Preferably, the system is configured to pulse the accelerator so as to provide the operator with a tactile indication of an operational state of the system and/or the vehicle. For example, the accelerator may pulse by simply moving back and forth, without significantly altering the power output of the motor, so as to inform the rider of a certain condition, such as when the system is being activated in conjunction with the traction control system of the vehicle.

In certain embodiments of the invention, the force applying means comprises electromagnetic means. In other embodiments of the invention, the force applying means comprises a motor such as a servo motor. The motor may be a stepper motor due to its relatively high holding torque.

Preferably, the resistance applied by the force applying means is adjustable. As such, the force required to be applied to the accelerator to overcome the resistance applied by the force applying means can be adjusted to suit vehicle operators of different strengths and sizes.

In various embodiments of the invention, the force applying means applies a frictional braking force between the accelerator and a component relative to which the accelerator moves when in operation. In one example, the frictional braking force is achieved by an engagement between corresponding teeth of the accelerator and the component.

It is envisaged that the accelerator system can comprise a manual actuator via which the operator can actuate the frictional braking force. The manual actuator could be mechanical, in the form of a lever for example, or electrical and in the form of an electrical switch. For ease of access, the actuator is preferably mounted on the accelerator of the accelerator system. The actuator may be resiliently biased to return to a rest position when it is not actuated by the operator.

Preferably, the accelerator is electrically connected to the motor of the vehicle to thereby control power output. The accelerator system may comprise a sensor for sensing the force applied by the operator to the accelerator wherein the input includes information relating to this force.

The accelerator system could also have one or more force sensors which can be actuated by the operator by applying pressure to the accelerator, wherein the pressure applied does not modify the power output of the vehicle motor. In the case where the vehicle is a motorcycle, the accelerator could be a twist throttle which is gripped by the operator, and the force sensor(s) can be provided on the twist throttle where the operator grips it.

In preferred embodiments of the invention, the accelerator of the system is a twist throttle. In such embodiments, the sensor comprises a torque sensor for sensing a torque applied to the twist throttle by the operator.

In certain embodiments of the invention, the force applying means is operable to lock the accelerator against manual operation which would increase the power output of the motor; and/or apply an increased resistance to manual operation of the accelerator which would increase the power output of the motor. In this way, the accelerator system acts to resist or prevent the operator from increasing the power output of the vehicle motor.

It is to be understood that the reference to a manually operated accelerator as defined above includes not only a hand operated accelerator but also a foot operated accelerator. It is also to be understood that the reference to vehicle motor as defined above includes not only internal combustion engines of various types but also electric motors as would arise in the case of battery powered vehicles.

Brief description of the drawings

The invention is now described by way of example only with reference to the accompanying drawings in which :

Figure 1 is a schematic view an accelerator system according to a first embodiment of the invention in conjunction with various components of a motorcycle;

Figure 2 is a plan view of an accelerator system according to a second embodiment of the invention;

Figure 3 is a plan view of an accelerator system according to a third embodiment of the invention;

Figure 4 is a plan view of an accelerator system according to a fourth embodiment of the invention; and

Figure 5 is a plan view of an accelerator system according to a fifth embodiment of the invention.

Detailed description

Embodiments of the present invention seek to improve a vehicle operator's control of a powered vehicle by giving them resistance to motion or effectiveness of, and possibly also feedback from, and movement of, the accelerator. The accelerator system could provide control over the steering of the vehicle as well as feedback from the steering mechanism to the vehicle operator. The accelerator system may also provide control over suspension components in order to achieve the overall goal of allowing the operator of the vehicle to better modulate the power delivery of the vehicle. The braking functions and clutch functions could also be incorporated.

The following example given generally employs what is a commonly used accelerator, known as a "twist grip" throttle, but the accelerator system could be applied to other form of accelerators such as a thumb actuated control or a foot actuated controls.

The position of a motorcycle rider and the forces imparted by the rider to the motorcycle help the rider control the motorcycle. With the rider in certain positions on the motorcycle, and under conditions such as accelerating, decelerating and also cornering, the rider's input to the motorcycle handle bar controls can be compromised. The present accelerator system seeks to improve the rider's ability to control the motorcycle under these conditions. This can also be applied to other powered vehicles where forces acting on the operator reduce the operator's ability to control the vehicle.

The twist throttle of a motorcycle is a flawed control as the rider needs to use this to both control the steering and the weighting of the bars as well as to regulate the power delivery. An example of this is when the motorcycle accelerates hard, the rider's weight is thrown back, this tends to open the throttle more making it difficult for the rider to both hang on and reduce the power being applied. The rider is able to pull back on the left handle bar without affecting the throttle but not the right and this tends to make steering the motorcycle more difficult due to the imbalance.

In a basic form, the present accelerator system, as applied to a motorcycle, has a degree of control over the twist throttle mechanism enabling the rider to have better control of the motorcycle by means of the handle bars. This could also be expanded to include control over a steering mechanism, a clutch mechanism and also braking mechanisms, all of which, in the case of a motorcycle, are actuated by the rider's hands.

Control over suspension can also be used to help the rider better control the motorcycle by handle bar means.

In an embodiment of the accelerator system as shown in Figure 2, a switch or lever, easily accessible to the rider, perhaps thumb-operated, can be used to lock the throttle drum 42 from being able to be rotated in relation to the handle bars 40, allowing the rider to pull on the handle bars without applying more power, or to maintain throttle whilst trying to prevent being thrown forwards. This throttle locking feature could be by mechanical means whereby pressure applied by the rider to a lever 4 or against a surface on the grip, prevents the throttle drum 42 from being rotated. This mechanism could incorporate a friction inducing means similar to a brake whereby the greater the pressure applied to the lever 4 or surface, a corresponding degree of friction or resistance to rotation is applied the throttle drum 42 to prevent it rotating. This mechanical means of preventing or resisting throttle rotation could also be achieved by means of a wedge 43 driven against a round section of the throttle drum 42 by the operator by any means, in order to generate friction or prevent rotation. This wedge 43 could be designed to generate more friction in one direction, for example so as to allow the rider to be able to close the throttle but not open it. This mechanism could include a cam and or a lever system that is used to generate pressure to apply more friction.

The friction required to lock or resist rotation of the throttle drum 42 could also be generated by the rider actuated control moving the throttle drum in line with the handle bars, as shown in Figure 3, pushing a friction surface 48 that is attached to the rotating throttle drum 42 against a friction surface 47 that is fixed to the throttle body 41 that, in turn is attached to the handle bars 40. The friction surfaces 47 and 48 could be a series of fine radially arranged teeth that mesh together offering a positive locking mechanism.

The lever 4 to facilitate the resistance to rotation or locking of the throttle could be incorporated into the rotating throttle drum 42 so as to allow the rider to easily actuate it in any throttle position. The lever 4 when pushed by the rider rotates around a pivot 46 that pushes via a bearing 51 against a section of the throttle body 41 this pulls the throttle drum 42 from left to right bringing the friction surfaces 47 and 48 in contact and thus helping to prevent throttle drum 42 rotate in relation the handlebars 40.

The mechanism could also be hydraulic in nature varying the damping applied to the rotation of the throttle. The rider actuation means could be incorporated into a section of the throttle grip, either left or right whereby the rider is able to resist or prevent rotation of the throttle by applying pressure to a specific position on the grip. The throttle locking mechanism could also have a means by which rotation of the throttle drum 42 is allowed freely in one direction but not in the other. This could be via a one way clutch method or by a ratchet means. Two separate levers, or surfaces, actuated by the rider could be used, one causing resistance or preventing rotation in one direction, and the other causing resistance or preventing rotation in the other direction.

These levers or surfaces could be on different sides of the handle bars, or this feature could be activated by the rider by any other means possible.

An electromechanical means of providing resistance to rotation or locking of the throttle could be employed whereby a solenoid could be used to apply a force to a braking or ratchet mechanism acting on the throttle. The actuation, or pressure applied to, the lever or surface, or by another lever or surface, by the rider, may also be arranged so as to increase the throttle opening either by mechanical or electrical means thus allowing the rider to increase the amount of power provided to the drive wheel or wheels of the vehicle without rotating the throttle.

With reference to Figure 1, a motor drive can be fitted to the accelerator and by inputting information supplied by various sensors and transducers to an Electronic control Unit 1, such as one using a microprocessor, and output a programmable response to drive a motor that can actuate, or apply a resistance to being actuated, to the throttle mechanism 2 of said vehicle, with the object of helping the rider better control the vehicle and also provide a mechanism to give the rider feedback. By providing feedback to the rider through the throttle it should be possible to reduce the overall rotation of the throttle required to effectively allow to rider to have good control over the power delivery, this will improve the ergonomics of the vehicle. This may also include the use of a "fly by wire" throttle or accelerator. Resistance to rotation of the throttle may be by mechanical means (see Figure 3 for example). When a "fly by wire" throttle is used the system could be programmed so that as a response to input from various sensors, when the throttle is prevented from being rotated by the system or by the rider locking the throttle by mechanical means, the power output is controlled via the "fly by wire" throttle to achieve a programmable outcome. For example when the throttle is locked in an open position above a certain degree the system could be programmed to maintain by means of "fly by wire" throttle maximum power possible whilst still maintaining traction.

In another form the throttle operated by the rider may not be a twist grip throttle but a mechanism whereby a torque sensor is mounted between the right hand handlebar grip and the handle bar and monitors the twisting force applied by the rider. This torque sensor may be actuated by only a specific portion of the grip, this portion of the grip may be formed in a raised section of the grip such as shown as reference numeral 45 in Figure 1 to give the rider a tactile location of its location. The output is fed into the Electronic control unit 1 which then actuates a fly by wire throttle 11 depending on the values of some or all of the sensors according to its programming. The Electronic Control Unit 1 may for instance reduce the sensitivity to throttle torque if it detects that the rider is being subjected to high acceleration forces and therefore their ability to control the throttle is compromised. The torque sensor could also be used in a clockwise direction to feed a signal to the Electronic Control Unit 1 that causes a braking function to occur via a servo braking system either rear or front or a combined actuation. The braking force distribution between front and back may be modified by the rider applying force to one or some of the pressure transducers in the grips 6, 7.

Pressure applied to one or some of these pressure sensors may cause the brake or brakes to be activated thus allowing the rider to drag the brake against the power. Likewise pressure applied to certain pressure sensors could be used to actuate a clutch function via a servo means.

The torque sensor may be between the handle bar grip and a motor driven tube or mechanism controlled by the Electronic Control Unit, so that feedback as described by the twist grip example can be transmitted to the rider.

The torque sensor actuated by the right hand grip could be only effective over a portion of the said grip, enabling the rider to both effectively control the power delivery and also maintain a degree of grip on the bars without causing unwanted acceleration or deceleration. The handlebar grips may have raised or shaped portions to give the rider a tactile indication of the location of pressure or torque sensors. These raised or shaped portions of the grip may be so shaped as to allow the rider to better be able to transmit force so as to be able to control the function whilst also improving handle bar grip. The controlled rotation of the grip and torque sensor by the Electronic Control Unit 1 may also be used to maintain the grip in a position that best matches the riders body position as determined by the Electronic Control Unit 1 as a response to inputs such as but not limited to the pressure sensors 6, 7, 17, 19, 20 and the torque sensor on the left handle bar grip 34 and also on the foot pegs 19, 20. The present accelerator system could also include motor driven steering used to both control the steering and also provide feedback to the rider.

Traction control systems typically are controlled by electronics but do not allow the rider to override them effectively in real time. Sometimes on a motorcycle wheel spin is desirable to enhance rider control of the motorcycle; embodiments of the present accelerator system enable the rider to override the traction control system in a measured way in real time. It also can alert the rider of a loss of traction, and by using algorithms and rate of change it could be used to alert the rider of impending loss of traction or an over rev situation. Information regarding the activation a traction control system could be inputted to the electronic control unit so as cause via programming, the rotation of the throttle to a position whereby traction is maintained. This could also be used to allow the rider to improve efficiency. The present accelerator system can also be used to enhance the rider's control of the motorcycle by preventing the throttle from rotating when not desired or possibly by rotating it in a required direction should an electronic control unit determine that this is required based on inputs and programming, so as to enhance the control of the rider over the vehicle or improve the stability of the motorcycle. This could also be incorporated to form part of a collision avoidance system and use radar and cameras as additional inputs. The system could employ a "fly by wire" throttle whereby the throttle actuated by the rider is not necessarily rotated by the system but power is changed by a separate motor driven throttle. In this situation the rider operated throttle may or may not be prevented from rotating, or rotated in, one or both directions according to the programming of the system in response to various inputs.

Inputs to the accelerator system could include, throttle position sensor, RPM, vehicle speed, gear selection, accelerometers, torque sensors for the propulsion of the vehicle, throttle torque sensor, gyroscopes, pressure sensors in the hand grips both left and right and in different positions of the grip, torque sensor measuring the twisting motion applied to the left hand grip able to measure and distinguish the direction clockwise or anticlockwise, inclinometer or angle sensors both longitudinal and traverse, current sensors, cylinder pressure sensors, left and right foot peg pressure sensors, left and right foot peg angle sensors, steering angle sensor, steering torque sensor, brake pressure front and back, suspension loading front and back, suspension position front and back, input and feed back to ABS or antilock braking system or a collision avoidance system, clutch position and pressure sensors, seat pressure or positional sensors in various positions on the seat, pressure sensors in various positions on the petrol tank or whatever surface is forward of the seat so as to allow the system to know the position of the rider, side stand switch, operator activated switches, radar, GPS, cameras, plus any other input that can help the Electronic Control Unit (ECU) determine an appropriate output to the motor that drives the throttle or accelerator in such a way to better inform the rider or improve their control over the vehicle. Rate of change of any input parameters and algorithms could be used by the ECU to help determine a predictive feedback to the rider. The pressure sensors could be used help the system determine the position of, and forces acting upon the rider, as well as being used by the rider to control the system. It is envisioned that the system will be able to be programmed by the operator to respond to any or all of the inputs from the sensors to a varying degree, to achieve a desired outcome outputted to the motor driven throttle and or a "fly by wire" throttle.

The motor driven throttle may incorporate a torque sensor so as to be able to determine the torque being applied to the throttle by the rider, so as to create a "closed loop" system to help the electronic control unit respond appropriately, and provide more accurate feedback to the rider. Likewise the steering could also employ this torque sensor and closed loop system.

In the example of a motorcycle rider being forced backwards relative to the motorcycle when accelerating, the present accelerator system could use inputs from force sensors on the front portion of the handle bar grips, throttle position sensor, accelerometers, suspension position and loadings, vehicle speed, inclinometers and others fed into the ECU that generates a measured and programmable response that via the motor driving the throttle resists the throttle rotating in a direction that applies more throttle. This helps prevent the rider from applying unwanted power that would have otherwise exacerbated the situation. The force applied by the motor that drives the throttle, can be adjusted by the operator.

It is envisioned that the rider would always be able to able to overcome this force to apply more power if they desired, but this may not be the case.

When a rider is going up a steep hill the input from the inclinometer to the ECU along with other inputs could increase the force resisting rotation allowing the rider to be able to pull their weight forward to prevent excessive wheel standing without applying unwanted power.

The throttle could also be in certain circumstances be closed by the motor for example if the input from certain sensors allowed the ECU to determine that the rider was not on the motorcycle or the motorcycle was too great a lateral or longitudinal angle or acceleration was determined to be too great, or in any circumstance that was programmed into the electronic control unit.

Another example of when the throttle may be closed by the system is by using input from a traction control system or using the inputs to the ECU to detect traction loss or impending traction loss are used to rotate the throttle back to a position where traction is maintained but the force (adjustable) is such that the rider is able to override the system and apply more power if desired. In the case of "fly by wire" throttles, or traction control systems that employ other means of power reduction such as retarding ignition and/or fuel cuts, the rider could choose to override some or all of these actions by not allowing the throttle to be rotated back by the motor or by applying more throttle.

This motor drive of the throttle could also be used to achieve a cruise control function but one that the operator is able to reduce the throttle as well as increase the throttle or accelerator overriding the system. In the case of a typical car accelerator this may involve a departure from the typical accelerator pedal used employing a "push pull" mechanism.

Another situation where the present accelerator system could assist the rider controlling the motorcycle is in the case off what is commonly known as a "Tank Slapper". This is a situation where an external input such as the motorcycle hitting a pot hole can initiate a condition whereby the handlebars can oscillate violently. When this happens the rider, trying to hold on to the handlebars can exacerbate the situation. As the right hand bar moves towards the rider the throttle tends to be closed and as the bar moves away from the rider the throttle tends to be opened. Being at the same frequency as the handle bar oscillation the rapid opening and closing of the throttle can feed back and make the situation worse. Often in this situation deceleration can be the worst thing to do because it makes the motorcycle less stable. By using inputs from various sensors such as the pressure sensors in the hand grips this situation could be detected by the system; for example it could be programmed to dampen or lock the throttle if the system detects changes from left to right forces above a certain frequency and/or amplitude. It is envisaged that the system would offer the rider the ability to be able to easily "tune" or program not only it's responses to the outputs of the various sensors, but also the outputs to the rider, given to the rider, by the motor driven throttle as well as possibly controlling the steering.

This system could also include an active steering damper 9 and active suspension 31, 32 activated to increase the damping effect to steering movement, or alter suspension damping or preload, or utilize motor driven steering 9 , when the system determines, according to is programmed response to various inputs. In the case of the active steering damper 9 the electronic control unit 1 could use the inputs from the grip sensors 6, 7, left hand grip torque sensor 34, and steering angle sensor 9 as well as other sensors to determine if the input to the steering was being applied by the rider or as a reaction externally generated forces, and control the amount of damping accordingly so as to improve stability. Rate of change of the sensors outputs could be used by the electronic control unit to help differentiate between rider input and forces generated by external means. The active steering damper 9 could employ a motor to actuate the steering or to provide the damping effect. The motor driven steering could be used to help counter the effects of the rapid oscillations of the handle bars experienced during a "tank slapper" by applying a force, or to position the steering, at such an angle determined by the programming of the Electronic control unit, so as to more quickly attain a more stable vehicle. The motor could be a steeper or servo motor or it could by hydraulic.

The steering may be to a degree "fly by wire" and not all the movement or forces may be fed back to the rider through the handle bars 40.

When accelerating or decelerating, the electronic control unit 1 could be programmed to provide resistance to steering motion, or to provide a force to the steering mechanism so as to stabilise the steering mechanism or even alter the steering angle so as to compensate for the fact that the rider is able to provide more force on his non throttle operating hand. In response to inputs to the electronic control unit 1 this system could be used to modify traction controls systems responses.

An example of this would be to program the system to alter the preload and or dampening of the suspension, and or the degree of damping applied to the steering, or position of the steering, under conditions based on inputs primarily but not necessarily exclusively, on forces being applied by the rider to sensors on the vehicle.

Another possible application would be by using inputs such as pressure sensors in the front portion of the handgrips, accelerometers 23, 24, suspension loading and position, to determine that the motorcycle has rapidly deaccelerated, and by using other inputs such as throttle position sensor 3, brake line pressure front 28 and back 29 or and input from other sensors, and programming the electronic control unit 1 to respond via the motor driven throttle 2 or locking mechanism, in order to prevent the throttle being shut if the rider is thrown forward . This could be used to help prevent forward weight transfer caused by the rapid closing of the throttle. The system could also be programmed to increase suspension preload and or dampening in this circumstance.

The system could in this circumstance be programmed to increase resistance to the steering angle being changed to further enhance stability and enable the rider to better control the motorcycle by means of the handle bars.

By using inputs from various sensors to detect rough terrain or situations that may affect the rider's ability to effectively control the throttle, or steering, the present accelerator system could either actively control the throttle or simply create a resistance to the throttle being rotated in either direction to improve the motorcycles rider's control and help prevent unwanted rotation of the throttle and likewise prevent unwanted steering input from the rider.

Figure 5 shows an example of the invention that works with a "fly by wire" accelerator system with a twist grip throttle arrangement that uses a Throttle Motor 55, that is directly connected to the Throttle Drum 42. Also connected to the Throttle Drum 42 is a Throttle Position Sensor 3; this could be a potentiometer or an encoder or any other type of sensor to inform the Electronic Control Unit 1 of its position. Also connected to the Throttle Drum 42 is a Torque or Force Sensor 53 for measuring the force exerted by the rider on the throttle. This sensor is positioned between the movable Throttle Drum 42, and the fixed Throttle Body 41. Depending on the nature of this force sensor this may be pivotally connected to either the Throttle Drum 42, or/and to the Throttle Body 41. The Torque or Force Sensor 53 may be arranged such that a spring is between the Throttle Drum 42 and one of the physical connections of the Torque or Force Sensor 53 to either the Throttle Body 41 or the Throttle Drum 42, such that as the Throttle Drum 42is rotated in a direction to apply more power, the pressure applied to the Torque or Force Sensor 53 is via this spring. At some point in the Throttle Drum 42 rotation the spring may bottom or a travel stop may be used such that at this point the force is directly applied to the Torque or Force Sensor 53. The ECU 1 could use the combination of the throttle position and the force applied by the rider to ascertain the amount of power to be applied to the wheel(s) of the vehicle.

Another way that this could be done is to have the Torque or Force Sensor 53 positioned between the Throttle Body 41 and the Throttle Motor 55 such that the Torque or Force Sensor 53 is measuring the force applied by the operator against the force applied by the Throttle Motor 55. Furthermore a stop that limits the movement of the Throttle Motor 55 and that is in effect the stop that limits the movement of the Throttle Drum 42 could be used such that when the Throttle Drum 42 is moved to this stop, the Torque or Force Sensor 53 is now measuring the force applied by the operator to the Throttle Drum 42 against the reactive force provided by the Throttle Motor 55 and also the force applied by the operator between the Throttle Drum 42 and the Throttle Body 41. By positioning the Torque or Force Sensor 53 in such a way the programmable ECU is able to determine how much resistance the operator is providing to the positioning of the Throttle Drum 42 as a result of the actuation of the Throttle Motor 55 by the programmable ECU 1. This information could be used via the programming of the ECU 1 to help determine if the operator desires to disable a function such as the traction control.

This arrangement could help to reduce the amount of movement of the Throttle Drum 42 required to effectively control the power. An example of how this result could be achieved could be to have a combination or the force measured by the Torque or Force Sensor 53 and also the position of the Throttle Drum 42 as measured by the Throttle Position Sensor 3 via the programmable ECU 1 determine how much power the rider wants to apply to the driven wheel(s). The Programming of the ECU 1 could be such that the initial power is determined predominately as a result of position and then once a certain power level is achieved then it is predominately as a result of the force measured by the Torque or Force Sensor 53. The force to the Throttle Drum 42 provided by the Throttle Motor 55 as a result of the programming of the ECU 1 gives the rider feedback as to operating conditions of the vehicle as well as providing resistance to the rotation of, or movement of the Throttle Drum 42 as deemed by the programming of the ECU 1, in order to allow the operator to have better control over the power applied by the vehicles motor.

Figure 4 shows a similar arrangement to Figure 5 but employs a solenoid to provide the force supplied previously by the Throttle Motor 55 and the positioning of the Torque or Force Sensor 53, as well as the spring placed between the Torque or Force Sensor 53 and the Throttle Drum and also the travel stops associated with the system could be as described previously.

In all examples a return spring could be used so as to return the Throttle Drum 42 to a position that represents an idle or no power position as is typically employed in a throttle or accelerator mechanism.

Bearings could be used to support the Throttle Drum 42 in relation to the Throttle Body 41 so as to allow less friction in relation to the movement of the Throttle Drum 42 as well as more accurate positioning of elements of the system that move.

For simplicity, Figures 4 and 5 do not show all of the inputs or outputs to the ECU 1, or the Traction Control System; examples of the inputs and outputs to the ECU 1 that could be used, are depicted in Figure 1.

Also to simplify Figure 1 the normal inputs to the Traction Control Unit (18) are not shown.

When force sensors are used in the case of hand grips these could consist of Force-Sensitive Resistors placed between the hand grips and the Throttle Drum 42 or the Handlebars 40.

In the case of the sensors on the throttle side the electrical connection to these could be by means of flexible wiring, or by commutator means contained within the Throttle Body 41. Thin film conductors could be used to conduct electrical signals on the surface of the Throttle Drum 42.

In all examples of the invention employing an electromechanical means of moving the operator actuated accelerator, monitoring the current drawn by the electromechanical means in relation to other of its operation conditions, could be used to provide information for the ECU 1, via its programming, to determine the force being applied to the accelerator by the operator whilst the electromechanical means is activated by the ECU 1.

Elements or components that the ECU unit could have:

Analog-to-digital converters

Digital-to-analog converters

Signal conditioners

Processors

Signal generators

Comparators

Power supply

Discrete Inputs

Frequency Inputs

Analog Inputs

Analog Outputs

Frequency Outputs

Switching Outputs

Memory, Flash

Memory, Ram

Stepping motor drive circuitry

Motor or solenoid drive circuitry

Relays

Oscillators

The electrically actuated Fly By Wire Throttle 11, is controlled by the ECU 1 according to programmed responses to inputs from sensors that are related to operating conditions of the vehicle and/or relating to inputs from the operator. Other vehicle systems such as the Traction Control System 18 may directly influence the movement of the Fly By Wire Throttle 11 or an output from the Traction Control System 18 may be used as an input to the ECU 1.

Examples of the programming instruction outline are given below:

Is the operator currently actuating the throttle locking lever or switch? Inputs:

• throttle locking lever mechanical

• throttle locking switch

No - the system takes no action.

Yes - resistance is applied to the operator applying more power.

Outputs:

• throttle locking mechanism

• throttle friction inducing mechanism

• solenoid

• solenoid to actuate throttle locking mechanism

Has the traction control system been activated or about to be activated? Inputs:

• output from traction control system indicating its activation

• operator actuated throttle position and/or force sensor

• fly by wire throttle position sensor

No - the system takes no action.

Yes - resistance is applied to the operator applying more power, or the force required to be applied by the operator to the to increase the power applied is increased, the resistance to motion of the throttle could be pulsed so as to provide tactile indication to the operator as to the systems activation.

Outputs:

• throttle locking mechanism

• throttle friction inducing mechanism

• throttle motor drive unit

• signal sent to fly by wire throttle

• solenoid To what degree has the traction control system been activated?

Inputs:

• output from traction control system indicating its degree of activation

• throttle position sensor

• gear sensor

• vehicle speed sensors

• accelerometer

• operator actuated throttle position and/or force sensor

A comparison is made between the throttle position and the degree that the traction control system is reducing the power output and the motor moves the throttle to a position that according to the programming of the ECU, including possibly using look up tables, matches the power reduction measures taken by the traction control system. The system would be constantly monitoring this and moving the throttle accordingly. The motion of the throttle could be pulsed so as to provide tactile indication to the operator as to the systems activation.

Outputs:

• throttle motor drive unit

• fly by wire throttle drive motor

Has the operator moved the throttle to a position that would apply more power by overcoming the resistance provided by the throttle motor or has the operator applied a force to the throttle that exceeds parameters set by the ECU?

No - the system continues to provide resistance to the movement of the throttle or to move the throttle to a position according to the programming of the ECU, including possibly using look up tables, matches the power reduction measures taken by the traction control system or the system maintains the power via a fly by wire throttle that the programming of the ECU would normally apply. The motion or resistance to motion of the throttle could be pulsed so as to provide tactile indication to the operator as to the systems activation.

Yes - a comparison between the position of the throttle as determined by the throttle position sensor and the target position according to the programming of the ECU is made, and if the difference is greater than a predetermined amount then the system deactivates the traction control system power reduction measures until such time as the traction control system ceases to try to apply power reduction measures. This deactivation of the traction control systems power reduction measures could also be triggered by means of the throttle torque sensor exceeding a predetermined value or a combination of both position and measured force. Both the position difference value and the allowable force measured by the throttle could also be altered in real time as a result of inputs from load sensors that indicate that the operator has imparted this force or movement as a result of their position on the vehicle or as a result of acceleration forces acting on them. The system may or may not continue to provide resistance to the movement of the throttle or to move the throttle to a position that according to the programming of the ECU, including possibly using look up tables, matches the power reduction measures taken by the traction control system. The ECU may be programed to reduce the force provided by the throttle motor. The motion of the throttle could be pulsed so as to provide tactile indication to the operator as to the systems activation.

Has the vehicle reached a set speed or the speed limit?

Inputs:

• output from traction control system indicating its degree of activation

• throttle position sensor

• torque or force sensor

• gear sensor

• engine rpm

• vehicle speed sensors

• gps

No - the system takes no action.

Yes - resistance is applied to the actuation of the throttle to prevent the operator applying more power.

Outputs:

• throttle motor drive unit

• throttle locking mechanism

• solenoid

Has the vehicle exceeded the set speed or the speed limit?

Inputs:

• output from traction control system indicating its degree of activation

• throttle position sensor • torque or force sensor

• gear sensor

• vehicle speed sensors

• wheel torque sensors

• gps

• means to adjust a speed setting for the ECU.

No - the system takes no action.

Yes - a comparison is made between the throttle position and the degree that the speed has been exceeded and the motor moves the throttle to a position that according to the programming of the ECU, including possibly using look up tables, will achieve the target vehicle speed. Accelerometers, wheel torque sensors, and or rate of speed calculations could be used to anticipate an overshoot in vehicle speed and based on this the programming of the ECU generate a resistance to the throttle being rotated before the actual target speed has been exceeded.

In order to speed up the power reduction the traction control system power reduction measures may also be activated by the ECU so as to avoid exceeding the target speed value, the speed limit could be determined by means of using a GPS system and look up tables. The motion of the throttle could be pulsed so as to provide tactile indication to the operator as to the systems activation.

Outputs:

• throttle motor drive unit

• signal to activate the traction control power reduction measures

Has the operator of the vehicle been subjected to an acceleration that may cause unwanted movement of the throttle by virtue of their body being forced into a position that causes the throttle to move or cause unacceptable loads on their arm that actuates the throttle?

Inputs:

• output from traction control system indicating its degree of activation

• throttle position sensor

• throttle torque sensor

• vehicle speed sensors

• accelerometers • wheel torque sensors

• steering angle sensor

• suspension loading and position sensors

• GPS

• brake activation sensors

• load sensors activated by the operator

• gyroscope

No - the system takes no action.

Yes - the system resists the movement of the throttle in the direction that the ECU determines would have been caused by the operator as a result of forces imparted to the operator. An example of this would be to have the programming of the ECU be such that it via the throttle motor drive unit it generates a resistance to the rotation of the throttle that was proportional to the measured forward acceleration or possibly the measured torque being applied to the driven wheel of the vehicle. Another example would be to have the programming of the ECU be such that resists the closing of the throttle if the deceleration of the vehicle, or and the forces imparted to certain load sensors measuring the force imparted by the operator, or and suspension loading and position sensors, exceeded predetermined values. Another example would be to have the programming of the ECU be such that if an oscillation of forces is detected by the force sensors on the grips of the handlebars a resistance is applied to the rotation of the throttle as well as possibly sending a signal to an electronically controlled steering damper to increase the dampening. In all cases the torque being applied to the throttle could be monitored by the ECU and this compared to expected values based on computer modelling and the resistance to the throttle movement modified accordingly with the objective to offer the operator better power modulation of the vehicle.

Outputs:

• throttle motor drive unit

• throttle locking mechanism

• solenoid

• signal to activate the traction control power reduction measures

• signal to electronically controlled steering damper to increase the steering damping

• signal to suspension control mechanisms to dampen suspension motion. Is the rider off the vehicle whilst the vehicle is moving or the stand is not down or the vehicle is on an lateral angle that exceeds a pre-set value?

Inputs:

• throttle position sensor

• torque or force sensor

• vehicle speed sensors

• accelerometers

• load sensors activated by the operator

• stand activation switch

• angle sensors

• gyroscope

No - the system takes no action

Yes - the system closes the throttle to an idle position and or possibly a switch is activated that stops the engine from producing any power if the vehicle is determined to be moving or on an unacceptable angle when the load sensors indicate that the operator is not on the vehicle or is in such a position on the vehicle that it is determined according to the programming of the ECU that the operator is in a position that they have insufficient control over the vehicle.

Outputs:

• throttle motor drive unit

• solenoid

• signal to activate the traction control power reduction measures

• signal to the engine management system to shut engine down

Notes that apply to all programming examples:

• Not all inputs or outputs listed may have to be used by the system for any given programming example or other sensors could be used to help the ECU better respond to operating conditions.

• The throttle motor is mechanically connected to the throttle actuated by the operator this may be by direct coupling means or via a connection such as a push pull cable means.

• The throttle motor may be hydraulic, electromechanical, pneumatic, or of any nature that is able to resist or rotate the operator actuated throttle.

• the force that is provided by the throttle motor could be adjustable by the operator by means of a control knob, switches, or by means of programming changes. This could be used to enable the operator to always be able to overcome the force provided by the throttle motor.

• A one way drive connection could be provided between the throttle motor and the throttle so as to only permit the system to actuate the throttle in a direction that reduces power. This could be a ratchet type mechanism or a one way bearing or any other mechanism that allows the operator to move the throttle in a direction that reduces the power regardless of the system input via the throttle motor.

• A shear coupling could be used between the throttle motor and the throttle such that the operator has the ability to still actuate the throttle in the case of a system failure by using sufficient force to shear the coupling.

• a pulsed motion of the throttle motor may be used to help give the operator an indication that the system has been activated or to alert the operator of operating conditions. Different frequencies could be used to help to inform the operator of different operating conditions.

The motor drive for the throttle could be used to induce a pulsed motion of the throttle to alert the rider of other conditions for example low fuel or in the case of an electric vehicle low battery power. This pulsed motion could simply rotate the throttle back and forwards so as not to alter the throttle position significantly or it could be that the motion of the throttle induced by the system is stepped so as to inform the rider of a certain condition. Pulsed motion could be used to differentiate different conditions that the system is alerting the rider of, for example when the system is being activated for a traction control, a pulsed motion could be used to help alert the rider, a different frequency of pulsing could be used when resistance is being applied to prevent accidental throttle application, and likewise a different frequency could be used for alerting the rider of a dangerous operational condition. Another example of this would be to use this system to alert the rider of too high engine RPM and the impending actuation of a rev limiting system. The system could resist rotation of the throttle, possibly in a pulsed manner, when it detects torque being applied to the wheel or wheels, based on inputs such as engine wheel torque, current supplied to an electric motor, gear sensor, accelerometers, angle sensors, RPM of the motor, thus helping to inform, or if desired control, the amount of torque being applied to the driven wheel of the vehicle.

Pulsed motion could be introduced to the steering to alert the rider of certain condition such as tyre loading or lean angle. In a motor car feedback could be given to the driver via the steering wheel as to the forces being applied to the steering tyres, this feedback could be by means of a pulsed motion.

Input from by the rider to multiple grip sensors placed in different locations on the grip could be used to allow "on the fly" alteration the programming of the system by the rider as well as to control other functions, for example suspension or power settings.

A display screen 8, and or warning lights may be used to help the rider to program the system or inform the rider of current programming or provide information on what the system is doing or monitor sensor outputs. This screen could be a touch screen so as to help facilitate programming.

The motor drive for the throttle or steering, could be, but not limited to, a servo or stepper motor. It is envisioned that the motor drive would be directly attached to the throttle, or steering, but it could be remotely mounted and drive the throttle by for example, a push pull cable or hydraulic or any other suitable arrangement.

In all the examples of the present accelerator system the operator actuated accelerator could be considered to be an accelerator pedal as commonly used in a car. In this case the accelerator pedal could considered, purely in terms of functional description, to be a lever that is canter levered radially from the Throttle Drum 42.

Although embodiments described herein have specifically referenced motorcycles, the invention is applicable to other vehicles including cars.

While various embodiments of the present invention have been described above, it should be understood that they have been presented by way of example only, and not by way of limitation. It will be apparent to a person skilled in the relevant art that various changes in form and detail can be made therein without departing from the spirit and scope of the invention. Thus, the present invention should not be limited by any of the above described exemplary embodiments. Throughout this specification and the claims which follow, unless the context requires otherwise, the word "comprise", and variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated integer or step or group of integers or steps but not the exclusion of any other integer or step or group of integers or steps.

The reference in this specification to any prior publication (or information derived from it), or to any matter which is known, is not, and should not be taken as, an acknowledgement or admission or any form of suggestion that that prior publication (or information derived from it) or known matter forms part of the common general knowledge in the field of endeavour to which this specification relates.

Glossary of reference numerals

1 electronic control unit (ECU)

2 twist grip throttle or motor driven twist grip throttle

3 throttle position sensor

4 throttle locking mechanism and or switch

5 switches

6 left hand grip fitted on tube with pressure sensors

7 right hand grip fitted on throttle tube with pressure sensors

8 display screen

9 steering unit including motor drive, position and torque outputs and active damping control

10 engine throttle or power controller mechanically connected to 2

11 fly by wire throttle

12 motor

13 motor torque sensor

14 motor current sensor

15 cylinder head pressure sensor

16 rpm sensor.

17 seat fitted with a multitude of pressure sensors in fore and aft positions as well as left and right side pressure sensors

18 traction control system

19 left foot pressure and torque sensors 20 right foot pressure and torque sensors

21 vehicle speed sensor

22 G.P.S.

23 accelerometer longitudinal

24 accelerometer transverse

25 gyroscope

26 front wheel speed sensor

27 rear wheel speed sensor

28 front brake pressure

29 rear brake pressure

30 camera input

31 front suspension sensors loading and position and control transducers for damping and preload

32 rear suspension sensors loading and position and control transducers for damping and preload

33 gear selection sensor

34 left hand grip torque sensor

35 clutch activation and pressure sensors

36 servo rear brake system

37 servo front brake system

38 side stand switch

39 engine management system and or vehicle control system

40 handlebars

41 throttle body

42 throttle drum

43 wedge

44 throttle cable

45 raised formed section formed on handlebar grip

46 pivot

47 friction surface on throttle body

48 friction surface on throttle drum

49 spring

50 thrust bearing

51 bearing

52 throttle body torque or force sensor solenoid

throttle motor